Soils for Plumeria
A good plumeria potting mix is one that is fluffy, holds some moisture, has good drainage and gives plant roots the perfect balance of air, moisture, nutrition, and anchorage.
A good soil medium will hold water without letting it puddle up or drain completely through. Test the soil to see how well it drains.
How do you recognize quality?
Read the label and look for quality ingredients such as aged bark (or composted forest products), perlite, vermiculite, lime, sphagnum peat moss (not sedge peat), and no wetting agent (soil stays too wet for plumeria). Other ingredients might be gypsum, peat humus, and compost. Optional ingredients you don’t want are moisture-holding polymer and fertilizer. A few even include pesticides; avoid those for plumeria. Products labeled “bagged topsoil” and “compost” are cheaper, but reserve them for working into the ground, as they’re too heavy for pots or raised beds.
What about mixing your own soil?
A good simple mix for plumeria is 1/3 Peat, 1/3 Decomposed Pine Bark and 1/3 Perlite.
Or 1/4 Peat, 1/4 Coir, 1/4 Decomposed Pine Bark and 1/4 Perlite.
What about mixes with fertilizer included?
For best results, you’ll want to fertilize your plumeria with a quality balanced fertilizer in addition to using premium quality potting mix. Although many potting mixes contain fertilizer, most will be for flowering plants not trees and have too much nitrogen. It is better to feed your plumeria a balanced fertilizer with micronutrients (Whichever you pick, be sure to follow the directions on the label.) It is best to purchase a potting soil without added nutrients.
One way to test a soil is to see how it drains.
When soil is placed in a pot and watered, the water should start draining out within five to ten seconds. If the soil becomes soupy or water drips out slowly, you’ve chosen the wrong soil.